Removable plug for oil-wells



(No Model.)

G. P.`TADDBR. RBMOVABLB PLUG PoR OIL WELLS.

Patented vFeb. 23, 1897.

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GEORGE P. TADDER, OF M'ILLERSTOVN, PENNSYLVANIA.

REMOVABLE PLUG FOR OIL-WELLS.

SPECIFICATION forming part of Letters Patent No. 577,811, dated February 23, 1897. Application filed May 7,1896. Serial No. 590,635. (No model.)

To @ZZ whom t may concern:

Be it known that l, GEORGE P. TADDER, a citizen of the United States, residing at the borough of Millerstown, in the county of Butler and State of Pennsylvania, have invented a new and useful Removable Plug for Oil, Gas, Vater, and other Wells, of which the following is a specification.

The object of this invention is to provide a plug for closing the casing of oil, gas, or other wells in order to prevent ingress of water, mud, or other foreign substances during the process of repairing the casing when the sections thereof above the one in which said plug is located are removed, the invention embodying a bridge which is let down into the casing and engages the inner walls thereof to arrest or support the plug, devices for inserting and removing said bridge, and a check-valve located in the plug to permit the escape of oil or gas while preventing the ingress of water, mud, or cavings-in that may fall when the upper sections of the casing are removed.

Vith the above ends in view the invention consists in the construction and combination of the parts, as hereinafter set forth and claimed.

In the `accompanying drawings, forming part of this specification, Figure l is a vertical sectional view illustrating the bridge and device for inserting same in` casing, the said parts being separated. Fig. 2 is a vertical sectional view showing the plug in position for use. Fig. 3 is a side elevation of the device employed for removing the bridge. Fig. 4 is a similar View showing a modification of said device.

'The letter A designates a section of the cylindrical wellcasing, said casing being of the usual construction.

B designates a tube which forms a part of the plug proper, said tube being externally threaded at its upper portion for a considerable portion of its length to receive threaded collars or jam-nuts l) and b, which clamp in place a length of hemp rope B', that is coiled about the tube B and interposed between the collars or nuts. The opposing faces of these collars or nuts are beveled or undercut, as shown, to receive the end sections of the rope and hold them securely in place when the collars ornuts are tightened. The rope forms a packing which impinges against the inner side of the well-casing when the plug is inserted. The lower end of the tube B is threaded to receive a tapered or conical head B2, having an enlarged concavity adjoining the tube and communicating with a bore or vertical opening b2, that extends through the lower or smaller end of said head. A ball b3 is located within the concavity of the head and is of slightly larger diameter than the internal diameter of the tube B in order to limit its upward movement by contact with the lower end of said tube, the latter having notches h4 to permit the exit of gas or oil. It

will be noted that when the ball is seated in the bottom of the concavity of the headl it will effectually close the opening or bore b2, and thereby prevent water which may enter the casing passing below the plug.

It will be understood that the plug is placed in the well tube or casing or in the wall of the well below the leak, the location of said leak being ascertained in the usual manner, and in order to support said plug in its proper position I have provided a bridge consisting of a sleeve C, to which are riveted or otherwise attached a series of upwardly-projecting spring-catches O. The free ends of these catches are provided with beveled heads presenting sharp edges c, which impinge against the inner side of the well-casing or wall of the well and secure a rm hold thereon, the spring tendency of the catches increasing such impingement. In connection with this bridge I. employ a device for inserting same in the well-casing, said'device comprising an inverted cup l), attached to the lower end of a tube D of small diameter. In the act of inserting the bridge the free ends of the spring-catches O are brought together and passed into the cup, and when said catches are released the bridge will be held in engagement with the cup by the frictional contact of the catches therewith. The bridge is then lowered into the well-casing to the desired depth, and by letting down aweight or tube into the tube D it will strike the upper ends of the spring-catches and force them out of the. cup, thus permitting said catche to impinge against the well-casing.

IOO

When the bridge has been inserted, the

plug is let down, and the conical head thereof entering between the free ends of the springcatches will force them into better engagement with the well-casing or wall of the well and the parts supported thereby, as shown in Fig. 2. The sections of the well-casing above the plug may nowbe removed for repairs, and said plug will prevent ingress of water to the casing below the plug and will permit the exit of oil or gas around the ball. After the repairs have been made the plug may be removed by any ordinary spear adapted for the purpose, while the bridge is removed by either of the devices illustrated in Figs. 3 and 4.

In Fig. 3 the stem E is provided at its lower end with pivoted fingers e, which fall outward after being passed through the lower collar c2 of the bridge and engage said collar when the device is drawn upward.

In Fig. et the stem F is provided with integral spring members ff, having spear-heads presenting shoulders that engage the collar c2.

Having thus described the construction, operation, and utility of my invention, .what I claim as new, and desire to secure by Letters Patent, is-

1. In a plug for well-casings, the combination of a tube having an external packing, a conical head secured to the lower end thereof and provided with a concavity and with a longitudinal bore or vertical opening below said concavity, the lower end of the tube having notches, and a ball located within the concavity and adapted to have a slight play therein, substantially as shown and for the purpose set forth.

2. In combination with the bridge constructed as shown and described, of a device for inserting said bridge in a well-casing, comprising an inverted cup which contains the free ends of the bridge, and a tube or equivalent means attached to the cup, substantially as shown and described.

3. A plug for well-casings consisting of a tube having externally-threaded ends, a rope packing coiled thereon so as to overlie the threads on the upper portion of the tube, jamnuts carried by the tube so as to engage with the packing thereon, notches or recesses in the lower end of lthe tube, a hollow conical head carried by the lower end of the tube and provided with an internal valve-seat, a ballvalve adapted to rest upon the valve-seat and abut when raised against the notched end of the tube, together with a bridge or means to hold the plug in the casing having movable ends which engage with the conical head of the plug and with the inner wall of the casing, substantially as shown and for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

GEORGE P. TADDER.

NVitnesses:

J. W. EDMUNDsoN, W. E. LACKEY. 

